48

The definition of mortality rate that you've given does not match any practical definition I'm familiar with.* When people talk about the mortality rate of a disease, what they usually mean is the case fatality rate or the death-to-case ratio, which is simply defined as Nd / Ni, where Nd is the number of deaths attributed to the disease over a given time ...


33

If there was close contact, if the 90% rate is accurate, and if occurrence is independent in related individuals, then you would expect 0.10 * 0.10 = 1% of contacts with 2 potentially vulnerable people to result in neither person infected. 1% sounds rare, but rare events happen all the time, and 1% isn't even particularly rare. If you know 100 families, you'...


20

The equation you use for mortality is only really useful in the very long term for a known disease, when most cases have resolved. It's not very informative in the short-term, when the vast majority of total cases are neither deaths nor recoveries. Right now, the vast majority of people diagnosed have a mild illness and are very unlikely to die, but it ...


19

The only approved inhaled vaccine is the flu vaccine delivered intra-nasally. It uses a live attenuated virus. There are a whole list of people who should not receive it because it's a live virus, and it works better for children, but only is 40% effective for adults. The main issue is The intranasal LAIV, recommended for children above the age of 2 ...


15

What your government is proposing is a lot less than what was actually done in China. There, and perhaps that is still the case, large numbers of asymptomatic infected people were housed together in halls with only social separation between them, and masks to prevent others from infecting others. Your government is proposing to house the asymptomatic ...


14

To add to @BryanKrause's answer re: rare events happen all the time, the children are not out of the woods yet. The mean incubation time for a primary VZV infection (the clinical syndrome known as chicken pox) is 14 days, but often lasts up to 21 days (see Murray Medical Microbiology, Ch. 53). The father is infectious while shedding virus, usually via the ...


14

I'd like to chime in with an explanation of what exactly is wrong with the calculation offered in the question, rather than just saying "it's a wrong formula". Understanding the "whys" of the fallacy is important. So I'll try to answer your question from the math point of view. TL;DR: The root cause of the fallacy is that recovery takes much longer that ...


12

This event occurred in the US. In the US, enzootic (dog-to-dog) canine rabies virus has been virtually eliminated through vaccination and stray control programs, making wild animals the primary concern. It is quite true, as @EMT_Jedi stated, that rabies is usually caused by an animal's saliva, usually introduced by a bite (e.g. rabid cats, raccoons, etc.) ...


8

Apart from not getting infected due to pure chance (as mentioned already) there is one highly probable explanation (explanation, not overall chance). People get, but don't show it: asymptomatic infection Asymptomatic infection is unusual, but some cases are so mild, they go unrecognised. The primary viraemic phase is followed by a secondary viraemia to the ...


8

The hygiene hypothesis For some reason I hold the opinion that the immune system needs to be kept busy so it wont get weak In scientific terms, this is known as the hygiene hypothesis. It was proposed in 1989 by Strachan and is about whether people who have been exposed to a lower amount of pathogens in their childhood are more likely to develop ...


7

The Hepatitis B core antibody test is positive for IgG but negative for IgM indicating that you had the hepatitis B infection a while ago. The negative hepatitis B surface antigen test means that they are not detecting the hepatitis B in your blood when testing for the virus surface antigen. This means you've successfully cleared the infection to a very low ...


7

The virus causing COVID-19 infects the respiratory tract. It is spread in droplets of moisture when an infected person sneezes, coughs, and exhales. These droplets can be inhaled directly and can also end up on surfaces, where they can be picked up on your hands and then spread to your face. The WHO recommends hand washing and avoiding touching your face ...


6

There is evidence that delaying or refusing immunization puts children at risk of disease here and here. There is also evidence that delaying or spreading out MMR or MMRV in particular puts children at greater risk of reactions (febrile seizures), rather then reducing the risk. I'm not aware of any study demonstrating the opposite.


5

Mosquitos transmit the pathogens that cause malaria, filariasis, dengue, yellow fever, West Nile fever, Rift Valley fever, and dozens of other infectious diseases of humans, domestic animals, and wildlife Ross, Macdonald, and a Theory for the Dynamics and Control of Mosquito-Transmitted Pathogens You already mentioned malaria and West Nile. The others ...


5

Yes. There are a number of diseases that can be transmitted by rodents, and several of them can be quite serious. This is the list of diseases that can be directly transmitted by rodents according to the CDC: Hantavirus Pulmonary Syndrome Hemorrhagic Fever with Renal Syndrome Lassa Fever Leptospirosis Lymphocytic Chorio-meningitis (LCM) Omsk ...


5

According to the CDC (Center for Disease Control). Rabies is transmitted via saliva of infected mammals, bats in your case. You state that you were not bitten, and did not feel any type of liquid on your person. You also stated that you thoroughly washed afterwards. If you did not have any open wounds at that time, I wouldn't be too worried about the ...


5

Positively, no. HIV is not spread by mosquitoes. You cannot contract any disease from swallowing a mosquito. Here, is a very large list of all the things that you could have caught :) If you were bitten.


5

It's better to use some guidelines from reputable sources rather than coming up with your own. The WHO does not recommend masks for healthy people in most circumstances, only when directly dealing with someone infected, and in that case accompanied by careful hand washing. Their advice for the general public as of this posting (and this is good advice year-...


4

In general: No. Having ulcers does not protect you from catching the flu. But that "no" is an oversimplification. The devil is indeed in the details. The innate immune system and the adaptive immune system have to be considered. The reasoning given in the question is in principle largely only applicable to the innate system. The adaptive immune ...


4

Yes, E. coli is definitely contagious through direct contact. In fact your girlfriend's pyelonephritis could have come from you after sexual intercourse. The general mechanism for this would be that you had the pathogenic E. coli on your penis, and then it traveled up her urethra to the kidney. This is why there is a recommendation for women to urinate ...


4

Yes, daily sedation interruption means a break in giving the sedation therapy. According to a 2014 Cochrane review: Daily sedation interruption versus no daily sedation interruption for critically ill adult patients requiring invasive mechanical ventilation: Daily sedation interruption (DSI) is thought to limit drug bioaccumulation, promote a more ...


4

According to earlier answers, in this early phase of 2019-nCoV, Nd/(Nd+Nr) is an overestimator, and Nd/Nc is an underestimator. Since the currently bantered about rate matches the underwestimator Nd/Nc, you are correct that 2019-nCoV is more 'dangerous' than commonly claimed. I used quotes because dangerous a squirmy term. Noting that Nd/Nc equals Nd/(...


4

I think it's a great idea. It protects your eyes from respiratory droplets and keeps you from touching your face. I don't know how well it would work from keeping droplet from reaching your mouth, but probably pretty well, especially if you used it with an N95 respirator. It might be a little shocking/intimidating to people, so I would only use it in ...


4

The text does not say that more diluted bleach is more effective at killing viruses (or bacteria, or yeast, for that matter). I'm quoting: ...A tenfold dilution of bleach, which subsequently mixed with an equal volume of RSV-containing medium (so in fact a twentyfold dilution) eradicated all of the virus. A 100-fold dilution of bleach killed 100% of the ...


4

My research search-fu is rather weak, and it's also quite likely that such research doesn't exist as it's not really how latex (or equivalent) gloves work. The gloves will support infectious agents just as readily as your hands, but the benefit comes from the ability to take them off (I mean, you COULD take your hands off, but it's a bit excessive). Hand ...


4

If you are dealing with an infectious agent transmitted by bodily fluids, HIV or Ebola say, then gloves are an important element of personal protective equipment. Gloves help prevent infectious fluid from getting into cuts and scrapes on your hands. For air-borne and droplet transmitted pathogens the situation is more complicated. Improperly used, gloves ...


4

The story for these "common cold" coronaviruses is a slightly complicated. Mostly, these target different receptors (than the SARS family), except for NL63. The host receptor is a major determinant of pathogenicity, tissue tropism and host range of the virus. The S protein comprises of two domains: S1 and S2. The interaction between the S1 domain and ...


4

Where do you get the antibodies from? You could theoretically use donor blood from infected patients, but apparently it is still unclear if the transmission of those antibodies is safe. Also, those patients who generate the antibodies for everyone else couldn’t benefit from the treatment. And you‘d always need some who develop their own immune response. This ...


3

Incubation periods of common infections SKIN: Hand/foot/mouth disease..........3-6 days Measles, chickenpox..............7-21 days Rubella...................................14-23 days Lyme disease(Borrelia)..........3-30 days Scabies.....................................4-6 weeks Warts........................................4 weeks-6 ...


Only top voted, non community-wiki answers of a minimum length are eligible